Recently, memory systems comprising nonvolatile memories have become widespread.
As one of these memory systems, a NAND-flash solid-state drive (SSD) is known.
Because of their low-power-consumption and high-performance, SSDs are used as the main storage of various computers.
By the way, in data written to the SSD by the host, characteristics (i.e., data locality) where part of the data is rewritten frequently, and the remaining part is not rewritten frequently may exist.
Such data locality may increase the write amplification of the SSD, and may adversely affect the performance and life of the SSD as a result.